Figure 2. TGFβ-inducible SMYD3 correlates with Foxp3 expression in inducible but not in natural Treg cells.

(A) CD4⁺CD25⁺Foxp3^egfp+ nTregs and CD4⁺CD25⁻Foxp3^egfp− T cells were isolated from thymus of Foxp3^egfp mice. Smyd3 and foxp3 mRNA expression was analyzed by q-RT-PCR. (B) nTreg cells were isolated as in A and transfected with SMYD3 or control siRNA. After 24 hours smyd3 and foxp3 expression was analyzed. (C) Flow cytometric analysis of CD4⁺CD25⁺Foxp3⁺nTreg cells in thymus of SMYD3^−/− and WT mice. (D) Treg suppression assay comparing suppressive function of nTreg cells derived from WT and SMYD3^−/− mice co-cultured with CFSE-labeled WT naïve CD4⁺T cells stimulated with anti-CD3 and anti-CD28. Data are representative of 3 independent experiments and show means ± SEM of 4 replicates. *P<0.05, **P<0.01, ***P<0.001.